How often are you guys replacing the rubber hoses in your boats? I was draining my motor today to let it set up for a while, and the springs inside some of the hoses i pulled off were rusted and falling apart...is this basically the sign to replace? Aren't those metal bits gonna get shoved into my cooling system? I didn't realize there were springs in these things...halp!

The springs are to keep suction lines from collapsing. No biggy if they don't crush when you squeeze them with your hand. Look more at the rubber on the outside to see if it's cracked or aged. If you use a silicone spray on the rubber it lasts for a very long time.